This invention relates to sterilization with methoxymethane. More particularly, the invention concerns the sterilization of areas or articles contaminated by microorganisms, including foods and beverages, by contacting them with methoxymethane.
Sterilization of areas or materials ordinarily involves the application of stringent measures such as heating, adding chemical preservatives, chemical treating, or radiation. These stringent measures have substantial drawbacks, especially so far as foods and beverages are concerned. Sterilizing with heat requires elevated temperatures which are impractical for general application involving wide areas or large materials, and the heating also may cause undesirable alterations in the flavor and texture of the material sterilized, as in the case of foods and beverages. Chemical additives leave a residue and may change the appearance and taste of the sterilized material, as chemical treatment may also, as in the case of sulfur dioxide treatment of food such as raisins and dried prunes and beverages such as wines. Radiation causes flavor and texture alterations as well as involving various operating difficulties that make it hazardous to use.
This invention also relates to the extraction of normally solid foodstuffs, such as meat and vegetables, as distinct from liquid, such as milk and fruit juices, with methoxymethane, also called dimethyl ether, to remove water and fat as well as other materials soluble in the dimethyl ether, for example, cholesterol.
As obtained from natural sources, such as from animals, vegetables, fungi, bacteria, or algae, food is mainly composed of four classes of substances. These are protein, fat, carbohydrates, and water. In its natural form, food has a tendency to spoil; some of its ingredients are considered undesirable from a health standpoint; and its often substantial water content not only facilitates spoilage but also contributes undesirable bulk and weight, which makes its transportation more difficult and costly. These problems have been recognized for many years. Foods have been preserved by drying even by primitive peoples. Sterilization and canning are now common practice. More recently, freeze drying has proved to be effective but costly. Within the last century, nonfat dried milk has become a major article of commerce worldwide.